org.apache.lucene.search
Class PositiveScoresOnlyCollector

java.lang.Object
  extended by org.apache.lucene.search.Collector
      extended by org.apache.lucene.search.PositiveScoresOnlyCollector

public class PositiveScoresOnlyCollector
extends Collector

A Collector implementation which wraps another Collector and makes sure only documents with scores > 0 are collected.


Constructor Summary
PositiveScoresOnlyCollector(Collector c)
           
 
Method Summary
 boolean acceptsDocsOutOfOrder()
          Returns true iff this Collector can accept documents given to Collector.collect(int) out of order.
 void collect(int doc)
          Called once for every document matching a query, with the unbased document number.
 void setNextReader(IndexReader reader, int docBase)
          Called before collecting from each IndexReader.
 void setScorer(Scorer scorer)
          Called before successive calls to Collector.collect(int).
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

PositiveScoresOnlyCollector

public PositiveScoresOnlyCollector(Collector c)
Method Detail

collect

public void collect(int doc)
             throws IOException
Description copied from class: Collector
Called once for every document matching a query, with the unbased document number.

Note: This is called in an inner search loop. For good search performance, implementations of this method should not call Searcher.doc(int) or IndexReader.document(int) on every hit. Doing so can slow searches by an order of magnitude or more.

Specified by:
collect in class Collector
Throws:
IOException

setNextReader

public void setNextReader(IndexReader reader,
                          int docBase)
                   throws IOException
Description copied from class: Collector
Called before collecting from each IndexReader. All doc ids in Collector.collect(int) will correspond to reader. Add docBase to the current IndexReaders internal document id to re-base ids in Collector.collect(int).

Specified by:
setNextReader in class Collector
Parameters:
reader - next IndexReader
Throws:
IOException

setScorer

public void setScorer(Scorer scorer)
               throws IOException
Description copied from class: Collector
Called before successive calls to Collector.collect(int). Implementations that need the score of the current document (passed-in to Collector.collect(int)), should save the passed-in Scorer and call scorer.score() when needed.

Specified by:
setScorer in class Collector
Throws:
IOException

acceptsDocsOutOfOrder

public boolean acceptsDocsOutOfOrder()
Description copied from class: Collector
Returns true iff this Collector can accept documents given to Collector.collect(int) out of order.

NOTE: some collectors can work in either mode, with a more efficient implementation for in-order docs collection. If your collector can work in either mode, it is recommended that you create two variants of it, since some queries work much faster if out-of-order collection is supported by a Collector.

Specified by:
acceptsDocsOutOfOrder in class Collector


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